I have possibly found an issue that could be a potential problem to the apparel achievement. When I joined my brothers server a while back it gave me his entire apparel collection which I thought nothing of at the time until now. Perhaps his direct apparel going into my collection without me earning the apparel myself broke the game reading the apparel as a false entity. So everything I acquired from him is obsolete thus denying me the achievement. I have 279 apparel yet the achievement is still not registering. Might be a long stretch but worth noting. Perhaps it may help with the bug. Feel free to share your opinions as well so we may exchange potential reasons. Hopefully this helps.